Noise code communications systems are well known and are particularly desirable because they exhibit an immunity against self-interference and jamming. Noise coded means that the information is coded with a code that is "noise like" in that it will compress to an impulse when detected with a matched filter. In particular, one class of noise codes are known wherein pairs of coded signals termed "code mates" have autocorrelation functions which provide a peak output at a given time and a zero output or outputs having the same magnitude but opposite polarity at all other times. When code mate signals, for example, are multiplexed, matched filter detected, and linearly added, there is provided a lobeless impulse output of a relatively high amplitude at a given time and a zero output at all other times. Such codes and systems utilizing such codes are typically shown and described in U.S. Pat. No. 3,461,451, entitled, "Code Generator To Produce Permutations Of Code Mates", which issued to F. S. Gutleber on Aug. 12, 1969; U.S. Pat. No. 3,634,765, entitled, "System To Provide An Impulse Autocorrelation Function . . . Of One Or More Of Said Code Signals", which issued to F. S. Gutleber on Jan. 11, 1962; and U.S. Pat. No. 3,908,088, entitled, "Time Division Multiple Access Communications System", which issued to F. S. Gutleber on Sept. 23, 1975.
In the above mentioned related application entitled, "CW Interference Cancelling System For Spread Spectrum Signals", there is disclosed an interference cancelling system for continuous wave (CW) or slowly varying continuous wave signals appearing in a noise coded communications system which are eliminated by means of a variable delay line and a linear adder coupled to the output of the receiver prior to matched filter detection and which operates to provide an interference signal from the input interference signal which is exactly 180.degree. out of phase with respect to the input interference signal, which by adding the delayed interference signal to the input interference signal in the linear adder results in total cancellation of the interference signal while the signal level of the noise coded communications signal remains unchanged.